Chelsea will welcome Manchester City to Stamford Bridge tonight (January 5) in the Premier League. Graham Potter's men are in desperate need of a win, languishing in tenth place in the standings.Meanwhile, Vasco da Gama director Paulo Bracks has said that Brazilian prodigy Andrey Santos is having a medical in London. Elsewhere, the Blues are interested in a French forward.On that note, here's a look at the key Chelsea transfer stories as on January 5, 2023:Andrey Santos having medical in London, says Paulo BracksPaulo Bracks has said that Andrey Santos is having his medical with Chelsea. The highly rated Brazilian teenager is a target for the Blues, who're looking to bring in talented young players to the club. Santos has caught the eye with Vasco da Gama and is tipped to have a great future.Fabrizio Romano@FabrizioRomanoChelsea have completed the signing of Andrey Santos, documents are signed and sealed on both player and club side with Vasco. #CFC 📸 Here's Andrey is in London with his family, time for the medical tests and official statement.Chelsea will pay €12.5m fixed fee.312333014Chelsea have completed the signing of Andrey Santos, documents are signed and sealed on both player and club side with Vasco. 🔵🇧🇷 #CFC 📸 Here's Andrey is in London with his family, time for the medical tests and official statement.Chelsea will pay €12.5m fixed fee. https://t.co/qF0AW978JQRecent reports have hinted that the London giants have completed the move. However, speaking to the press, Bracks said that the transfer is not yet over the line."Andrey, he’s in London having the medical. Vasco accepted Chelsea’s proposal, but the deal is not closed. Between a proposal made and accepted until finalisation; there is no manual of days. It can take a week, 15 days, 30 days. It is important to point out because I understand the anxiety, but negotiations are complex,” said Bracks.Potter is expected to oversee a long-term project at Stamford Bridge.Chelsea interested in Marcus ThuramMarcus Thuram (right) is wanted at Stamford Bridge.Chelsea are interested in taking Marcus Thuram to Stamford Bridge, according to Si & Dan Talk Chelsea via Caught Offside. The French forward has been very impressive for Borussia Monchengladbach this season, racking up 13 goals and four assists from 17 games across competitions. The 25-year-old also caught the eye with Les Bleus at the 2022 FIFA World Cup in Qatar.Hrach Khachatryan@hrachoffChelsea are monitoring the situation of Borussia Monchengladbach forward Marcus Thuram.He will be free agent this summer.#CFC78445Chelsea are monitoring the situation of Borussia Monchengladbach forward Marcus Thuram.He will be free agent this summer.#CFC🔵🚨 https://t.co/3pOTBh9gkeThuram has entered the final six months of his contract with Monchengladbach, who have failed to convince him to extend his stay. The Frenchman is likely to be available for a cut-price deal this month, and the Blues are interested.Kai Havertz, Christian Pulisic and Hakim Ziyech have failed to impress recently and have all been linked with a move away from the club. The London giants are willing to let them leave for the right price, and Thuram could be an upgrade on the trio.Graham Potter remains coy on January plansGraham Potter has refused to divulge any transfer plans for the month. Chelsea are expected to invest in the squad after falling behind in the race for the top four in the Premier League. The Blues have already been linked with quite a few players in various positions.Fabrizio Romano@FabrizioRomanoGraham Potter on Badiashile deal done: “Until somebody tells me anybody has been signed, it would be unfair of me to comment”, tells @SkySportsPL. #CFCBadiashile will be in London on Monday to sign the six-year and half deal after medical tests. It’s almost completed.178741112Graham Potter on Badiashile deal done: “Until somebody tells me anybody has been signed, it would be unfair of me to comment”, tells @SkySportsPL. 🔵 #CFCBadiashile will be in London on Monday to sign the six-year and half deal after medical tests. It’s almost completed. https://t.co/nRedD0L1cwHowever, speaking to the press, Potter gave little away when asked about his plans for January."The problem is that if I answer it, and I’m specific with the answer then every single player in that area will be linked with Chelsea, so I have to dodge it. I’m the head coach, so my responsibility is to the players that are here, and then we’ll try to improve in every window," said Potter.He added:"January is a complicated one because it’s the middle of the season, and in the meantime, we have to deal with all the noise of Chelsea being linked with everybody. I won’t comment on anyone who isn’t a Chelsea player, but always my job is to help the players that are here and then support the club in terms of decisions they make in trying to improve.”The London giants have reportedly struck a £30 million deal to bring Benoit Badiashile from Monaco this month, although an official confirmation is pending.